Giardia are parasitic protozoans or single celled organisms that cling to the surface or float in the mucus lining of the intestines of mammals including our four-legged friend, the dog and ourselves. It is the most commonly identified intestinal parasite in North America and can be found throughout the world.
The parasite is transmitted through fecal matter. Once through the motile feeding stage, it develops into a cyst while traveling through the large intestine. Once outside of the host, the cyst can live in a moist environment for up to several months. Because of the cyst requiring a moist or even wet environment, the most common for an animal or human to ingest Giardia is through contaminated water. Streams, lakes, swimming pools, hot tubs, rivers or wells can all be host to the organism although contaminated food can cause the infection.
The infection, Giardiasis or beaver fever‘ is it is frequently called, causes’ diarrhea, abdominal cramping, gas, bloating, frequent pale and loose mucous stools, nausea, weight loss and overall listlessness. Gestation for the infection is 7 to 10 days and symptoms commonly last between three and twenty-five days with severe cases lasting months.
For diagnosis, a stool sample is required although that is not always conclusive if there are no cysts present. Several samples may be required depending on the severity of the infection as cysts are only passed periodically. Treatment is one of two antiprotozoal medications and support dogs dehydrated from severe diarrhea and nausea require I.V. fluids and hospitalization. If cysts are found in your pet’s stool, he should be treated even if he is symptom free and shows no clinical signs.
In healthy adult dogs, Giardia symptoms are usually mild and with treatment, recovery is quick. In the young, old or infirm, however, the infection is much more dangerous and must be treated seriously.
Recently a Giardia vaccine has been licensed in North America and studies have shown it to be effective in some cases of Giardia but not all. Ask your veterinarian for more information on this and any other vaccine.
Preventing Giardia is difficult with dogs as the only way to kill the cysts in contaminated water is to boil the water or filter it. Since dogs live for the moment and will not wait for water to boil or filtering to take place before drinking from a lake, stream or swamp, the chance of them ingesting cysts is far greater for them then it is for humans. Therefore, if you feel your dog could have come in contact with contaminated water seven to ten days ago and they are beginning to show symptoms, get them to the vet right away. Early treatment does help limit the impact the infection will have on your pet, and your pocketbook!